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41.
A 16-y-old boy who had undergone bone marrow transplantation for relapsed acute lymphoblastic leukaemia developed liver cirrhosis and refractory ascites, which did not respond to salt restriction, diuretics and abdominal paracentesis. Liver transplantation was not feasible because of poor nutritional status, pre-existing renal dysfunction and uncertainty about the prognosis of his leukaemia. The patient underwent a successful transjugular intrahepatic portosystemic shunt (TIPS), with immediate resolution of ascites, enabling cessation of diuretics and improvement in nutritional status. At 24 mo following TIPS there has been no re-accumulation of ascites. CONCLUSION: TIPS may have a role in the management of refractory ascites secondary to liver cirrhosis in selected children.  相似文献   
42.
目的 探讨双侧唇裂继发畸形的解剖学修复。方法 采用埋没导引缝合针缝合法 ,对于引起畸形的主要因素 :鼻翼软骨向两侧移位 ,鼻降肌挛缩 ,口轮匝肌移位 ,鼻孔底瘢痕挛缩等进行彻底松解后 ,牢固准确地复位、固定 ,以恢复其正常的解剖关系。结果 自 1998年以来 ,共收治 2 6例双侧唇裂继发畸形患者 ,除 1例叉状皮瓣远端坏死外 ,余均顺利成功。随访 1~ 2年效果满意。结论 本手术不仅简单省时 ,而且能达到从解剖学角度修复畸形  相似文献   
43.
Gastrointestinal teratomas are uncommon, benign neoplasms that occur primarily in children. A retrospective review of five cases (two gastric, one pancreatic, one mesenteric, and one in the lesser omentum) is presented with emphasis on the computed tomographic and ultrasonographic appearances. Principal findings are a well-defined mass with separate cystic and solid components of varying proportions, discrete areas with densities similar to that of fat, or coarse, globular calcifications within the solid component. Recognition of these findings may allow the radiologist to make a correct preoperative diagnosis of teratoma.  相似文献   
44.
Swett  HA; Fisher  PR; Cohn  AI; Miller  PL; Mutalik  PG 《Radiology》1989,172(2):487-493
Conventional computer-based medical expert systems deliver advice to physicians as written text. While such advice is useful, it has distinct limitations in a visually oriented discipline such as diagnostic radiology, in which decisions often depend on pattern recognition and appreciation of subtle morphologic features. The authors developed a prototype expert computer system, IMAGE/ICON, which displays groups of images sorted into a series of axes based on different ways in which they may be similar. They may share a common feature, group of features, causes, or clinical setting. IMAGE/ICON may display examples of morphologic variations of a dominant finding or a spectrum of abnormalities seen in an specific disease or group of diseases. The system also assembles a written analysis of key features of a case. Such a tool may be useful as a diagnostic aid or for continuing medical education. It is likely to have particular impact in the form of an intelligent radiologic workstation, as picture archiving and communication systems become available.  相似文献   
45.
A new tray has been designed for use during procedures involving needles and other sharp objects. The tray includes a foam adhesive pad, marked into 10 sections, into which the sharp objects can be placed point first. After the procedure, the objects can be safely withdrawn by their handles and then discarded. The tray has been used in more than 250 procedures.  相似文献   
46.
47.
Monitoring for undertransfusion   总被引:1,自引:0,他引:1  
BACKGROUND: Most published reviews and audits of blood and blood component transfusion have focused on the issue of overtransfusion and on the inappropriate use of red cell components. There is growing concern that efforts to curb unnecessary transfusions may result in a trend toward undertransfusion of patients. There is little published information that addresses this issue or the magnitude of this practice. STUDY DESIGN AND METHODS: Undertransfusion was evaluated by examining the transfusion records from a 3-month period for 55 patients who met the study criteria of having either a hemoglobin level < 7 g per dL or a platelet count of < 10 × 10(9) per L. If the identified patient did not receive a transfusion within 24 hours of the reported hemoglobin level or platelet count, the medical record was reviewed by a resident physician. RESULTS: A total of 213 individual hemoglobin levels and platelet counts, representing the 55 patients, met our transfusion criteria. All except 8 of the identified patients received red cells and/or platelet transfusions. Reasons for not transfusing red cells included the patient's response to nutritional support and iron supplementation, refusal of blood, and noncompliance. Reasons for not transfusing platelets included falsely low platelet count because of platelet clumping in vitro, contraindication based on clinical diagnosis (e.g., immune thrombocytopenic purpura), and the patient's death before transfusion. CONCLUSION: Red cell and platelet transfusions were appropriately ordered for all patients who met the transfusion criteria. Undertransfusion is not a problem at this institution according to the criteria established. It is recommended that other institutions expand their blood utilization audits to include investigation for evidence of undertransfusion. Further research regarding the issue of undertransfusion is warranted and could be expanded to include other components.  相似文献   
48.
We investigated the efficacy, safety and tolerability compared with placebo of a second dose of oral sumatriptan 100 mg in 1349 general practice patients who had already treated a moderate or severe migraine headache with 100 mg sumatriptan 4 h earlier. Headache was relieved by the first sumatriptan dose in about 70% of patients, but the second dose did not produce significantly more relief than placebo, either in nonresponders or in the group as a whole, nor did it reduce other symptoms (photophobia, nausea, vomiting, etc,) at 8 h, or influence the incidence of headache recurrence. The drug was well-tolerated, and a further single dose was effective in treating recurrence after initial relief. A single 100 mg dose of sumatriptan is an effective acute treatment for migraine. A second dose should be reserved for treating headache recurrence.   相似文献   
49.
Gamma-aminobutyric acid (GABA) and glutamate are implicated in numerous neuropsychiatric and substance abuse conditions, but their spectral overlap with other resonances makes them a challenge to quantify in humans. Gabapentin, marketed for the treatment of seizures and neuropathic pain, has been shown to increase in vivo GABA concentration in the brain of both rodents and humans. Gabapentin effects on glutamate are not known. We conducted a gabapentin (900 mg) challenge in healthy human subjects to confirm and explore its effects on GABA and glutamate concentrations, respectively, and to test the ability of single voxel localized proton magnetic resonance spectroscopy (1H-MRS) to reliably measure GABA and glutamate in the visual cortex at the ultra-high magnetic field of 7 Tesla. Reproducibility of GABA and glutamate measurements was determined in a comparison group without drug twice within day and 2 weeks apart. Although GABA concentration changes were small both within day (average 5.6%) and between day (average 4.8%), gabapentin administration was associated with an average increase in GABA concentration of 55.7% (6.9–91.0%). Importantly, drug-induced change in GABA levels was inversely correlated to the individual''s baseline GABA level (R2=0.72). Mean glutamate concentrations did not change significantly with or without drug administration. In conclusion, localized 1H-MRS at 7 Tesla can be successfully applied to the measurement of GABA concentration and is sensitive to acute drug-induced changes in cortical GABA. Whether baseline GABA concentrations predict clinical efficacy of gabapentin is an area worthy of exploration.  相似文献   
50.
Primary infection with herpes simplex virus 1 (HSV-1) and varicella zoster virus (VZV) results in lifelong latent infections of neurons in sensory ganglia such as the trigeminal ganglia (TG). It has been postulated that T cells retained in TG inhibit reactivation of latent virus. The acquisition of TG specimens of individuals within hours after death offered the unique opportunity to characterize the phenotype and specificity of TG-resident T cells in humans. High numbers of activated CD8(+) T cells expressing a late effector memory phenotype were found to reside in latently infected TG. The T cell infiltrate was oligoclonal, and T cells selectively clustered around HSV-1 but not VZV latently infected neurons. Neuronal damage was not observed despite granzyme B expression by the neuron-interacting CD8(+) T cells. The TG-resident T cells, mainly CD8(+) T cells, were directed against HSV-1 and not to VZV, despite neuronal expression of VZV proteins. The results implicate that herpesvirus latency in human TG is associated with a local, persistent T cell response, comprising activated late effector memory CD8(+) T cells that appear to control HSV-1 latency by noncytolytic pathways. In contrast, T cells do not seem to be directly involved in controlling VZV latency in human TG.  相似文献   
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